When I am using the Jmeter I created multiple threads(More than 500) when I started for the more than 500 requests on the server in 10 Seconds, then I can't get any response and API goes fail and my computer lost the internet connection I have 8 GB RAM in my computer so I want to know its a server issue or the computer issue?
If your computer looses Internet connection most probably it's your computer issue, make sure that it has enough headroom to operate in terms of CPU, RAM, Network and Disk IO.
You need to have sufficient amount of resources as if JMeter won't be able to send requests fast enough - you will get false-negative results. You can check your operating system health using built-in monitoring toolchains or JMeter PerfMon Plugin
Another possible reason is that your actions can be considered a form of DOS Attack and being blocked by your organization firewall or your ISP, if your computer has enough resources you need to contact your network administrators or ISP support and let them know that you're about to conduct the load test so they won't block outgoing traffic for that particular endpoint and the anticipated timeframe of your test.
Use the above site to calculate the bandwidth required for 500 requests. Say u kept 500 concurrent users with usage high , then u need roughly 70mb/s network bandwidth.
If you are interacting with your API using internet ,you can send max of 4mb/s. The remaining packets will get que and you will feel like your internet have dropped
If your API is in local network, and doesn't need internet . Then check your Ethernet cards max limit.